The gripping element of the type described, for example, in international patent application WO-2008012596-A2 comprises two substantially flat gripping jaws hinged to each another to turn one with respect to the other about a given fulcrum axis between a clamping position and a releasing position of the aforesaid inlet duct and/or first edge.
The gripping elements of the known type described above have some drawbacks mainly deriving from the fact that such gripping elements are shaped to withhold the bag at only one of the two edges, they can correctly withhold the bag only when the second edge, i.e. the free edge, is arranged underneath the first edge, and therefore they do not allow to tip the bag and withhold it with the second edge over the first edge.